upsell
verb [ I or T ] uk/ʌpˈsel/ us/ʌpˈsel/
business specialized向上推销（试图说服顾客购买额外或者更昂贵的产品）
to try to persuade a customer who is already buying something to buy more, or to buy something more expensive
They are trained to upsell customers to a larger drink. 他们受到训练如何劝说顾客购买更大量的饮料。